Amazon.com, RIM, Chesapeake are market movers

NEW YORK (AP) -- Stocks that moved substantially or traded heavily Wednesday on the New York Stock Exchange and Nasdaq Stock Market:

NYSE

Chesapeake Energy Corp., up $1.14 at $20.11

Aubrey McClendon, the energy company's CEO, is leaving Chesapeake amid philosophical differences with its new board of directors.

Robert Half International Inc., up $2.21 at $35.74

The staffing company said fourth-quarter profit jumped almost 38 percent as demand grew for temporary and full-time workers.

Manpower Inc., up $3.23 at $51.78

Fourth-quarter net income dropped 16 percent at the staffing company, but its adjusted results topped Wall Street expectations.

MeadWestvaco Corp., down $1.30 at $31.63

Despite posting a fourth quarter profit, the packaging company's results fell short of what Wall Street expected.

Freescale Semiconductor Ltd., up $1.84 at $14.23

The chip maker reported fourth-quarter results and offered a first-quarter revenue forecast that topped Wall Street's expectations.

Nasdaq

Amazon.com Inc., up $12.41 at $272.76

The world's biggest online retailer impressed investors with strengthening profit margins in its fourth-quarter earnings report.

Research In Motion Ltd., down $1.88 at $13.78

Shares of the company fell after the smartphone maker's CEO introduced the long-delayed BlackBerry 10 in New York.

Copano Energy LLC, up $4.90 at $38.03

Kinder Morgan Energy Partners LP said it will buy the natural gas company for about $3.2 billion in stock.